Computational Numerical Prediction for Afterburning Blast Pressure Depending on Internal Explosion Locations in a Long Tunnel

Hun Ji; WooSeok Kim

doi:10.7734/COSEIK.2025.38.3.191

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2025 Vol.38, Issue 3 Preview Page Next Page

Research Paper

Computational Numerical Prediction for Afterburning Blast Pressure Depending on Internal Explosion Locations in a Long Tunnel 전산해석을 이용한 장대 터널 내부 폭발 위치변화에 따른 재연소 폭압 특성 변화 추정

30 June 2025. pp. 191-199

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Abstract

When analyzing the explosion of TNT (Trinitrotoluene) or similar explosives inside a long tunnel, the phenomenon of afterburning should be considered. The afterburning energy and duration must be appropriately applied to incorporate afterburning into the analysis. In this study, analysis conditions were validated through shock tube experiments conducted using a structure similar to a tunnel. Based on these validated conditions, the afterburning duration trends were analyzed with respect to changes in the explosion location along the tunnel's length. Furthermore, the results were applied to explosion analyses to examine the variations in internal overpressure and impulse within the tunnel. The analysis was performed using a modeled tunnel with a square cross-section, having an entrance area of 0.785 m². The results revealed that the afterburning duration increases steadily as the explosion location moves deeper into the tunnel, eventually converging at a certain point. Additionally, the explosion analysis incorporating the increasing afterburning duration indicated that the maximum internal overpressure increases with the inward movement of the explosion location but ceases to increase beyond a specific point.

Keywords

afterburning conditions

internal explosion

tunnel

detonation point

computational numerical analysis

길이가 긴 터널 내부에서 TNT와 같은 화약의 폭발을 해석할 때, 재연소 현상을 고려하는 것이 매우 중요하다. 재연소 현상을 해석에 반영하기 위해서는 재연소 에너지와 지속 시간을 적절히 적용해야 한다. 본 연구에서는 터널과 유사한 구조인 충격파관 실험을 통해 해석 조건을 검증한 뒤, 이를 바탕으로 터널 입구로부터 내부 폭발 위치 변화에 따른 재연소 지속 시간의 경향을 분석하였다. 또한, 이 결과를 폭발 해석에 적용하여 터널 내부 폭압과 충격량의 변화를 분석하였다. 해석은 입구 면적이 0.785m²인 정사각형 단면의 터널을 모델링하여 수행되었다. 분석 결과, 터널 내부 폭발 위치가 입구에서 깊어질수록 재연소 지속 시간은 일정하게 증가하며 특정 지점에서 수렴하는 경향을 보였다. 또한, 재연소 지속 시간 증가를 반영한 폭발 해석 결과, 터널 내부 최대 폭압은 폭발 위치가 내부로 이동함에 따라 증가하다가 특정 폭발 위치 이후로는 더 이상 증가하지 않았다.

키워드

재연소 조건

내부 폭발

터널

폭발 위치

전산수치해석

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Information

Publisher :Computational Structural Engineering Institute of Korea
Publisher(Ko) :한국전산구조공학회
Journal Title :Journal of the Computational Structural Engineering Institute of Korea
Journal Title(Ko) :한국전산구조공학회 논문집
Volume : 38
No :3
Pages :191-199
Received Date : 2025-03-18
Revised Date : 2025-04-08
Accepted Date : 2025-04-10
DOI :https://doi.org/10.7734/COSEIK.2025.38.3.191

Journal of the Computational Structural Engineering Institute of Korea ISSN:1229-3059(Print) 2287-2302(Online) 한국전산구조공학회 논문집

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